Know thy Enemy
by princessadita
Summary: Isabella Salvatore was well known for her charm, her good looks, and her ability to keep a secret. She's loved by both her brothers, adored by her boyfriend, and best friends with the enemy. What happens when her secrets begins putting her brothers new girlfriend in danger? Begining in season 2.


**Should I be starting a new story right now? Absolutely not. Will I be starting one anyways? Of Course!**

 **I've been binge watching Vampire Diaries for a a month or so (I'm on season 5 I think) and honestly this was an idea that I couldn't get out of my head. I hope you guys like it! Pls lmk if there's anything you'd like to see happen in this story, I don't have too much set in stone yet.  
**  
Isabella sat in her car staring at the sign, 'Welcome to Mystic Falls'. Memories of her childhood flashed by her as she internalized just how much everything had changed since she was a human. She shook her head a little as she started her jeep back up and drove by, trying to shake the thoughts out as well. Her chocolate brown hair whipped in the wind, and her icy blue eyes were covered by a pair of sunglasses. Even when she was human, her resemblance to her family was unmistakable. 'The Snippy Salvatore' was what they used to call her, seeing as she was never able to hold her tounge. It was fine for her twin, Damon, to do it seeing as he was a male, but during the 1800's it was improper for a woman to speak out of line. Her little brother, Stefan, was always better behaved. He listened to their father and was always the sensible one. She was pulling into the Salvatore Boarding House as she realized that she had gotten lost in her thoughts again. Rolling her eyes, she hopped out of the car and to the door. Upon entering, the house looked empty. Beautiful, as always, but empty.  
"Anyone home?" she yelled. Only seconds later she saw her twin standing in front of her smirking. "Hey Bells," he said, as he reached for a hug. He grabbed her around her waist, lifting her up and spinning her for a few seconds as she laughed and hugged him back. "What're you doing here?" he asked while putting her down.  
"Can't a girl come back home to see her two favorite brothers?" she responded.  
"We're your only two brothers, and seeing as you've known me longer, I'm your favorite" Damon remarked. Bella could only laugh at that. "Alright, busted, Stefan's been telling me a little about his new girl and I was curious. He's my baby brother, and seeing as you're not a great big one I had to come check her out"  
"Drink?" asked Damon as he led them into the sitting room, "please" she responded. "Also, I am an amazing older brother thank you very much" continued Damon, "obviously so amazing which is why I've only met your boyfriend over facetime. Most siblings wouldn't put up with that you know" he said with a small glare.  
"Oh hush, fifteen minutes does not make me a baby, and the only reason you've never met him in person is because you never come visit me!" she retorted as she stuck out her tongue. "So where's Stef?" she asked as Damon handed her a drink. Just as Damon was about to respond, the youngest Salvatore had appeared at the bottom of the stairs.  
"Stefan!" Squealed Bella as she ran up to her youngest brother. "How have you been?" She hadn't seen Damon in about five years, but it had been almost a decade the last time she had seen Stefan. "I'm good," he told her, "You look great Bells"  
"Thanks," she grinned at him, "you don't look too bad yourself for someone whos a hundred and something years old." Stefan chuckled, glad to have his sister home. While Damon was the twin he constantly fought with, Isabella was the sister who basically raised him. She was both a mother and a sister to him, and he loved her more than anything. Seeing as she was Damon's twin, however, she could be difficult when she wanted to be.  
"So where's this pretty little girlfriend you've been telling me about?"  
"Upstairs, getting ready"  
Bella's face turned to one of shock, "my little saint stefan?" she mocked, "has a girl in his bedroom? And she was, dare I say, naked"? She put a hand over her chest and leaned on the banister as she smothered a grin.  
"Ha ha, very funny. She's nervous to meet you, so please be nice"  
"And rightfully so," cut in Damon, "you're scary when you want to be, and trust me, you'll be mad about this one."  
"I'm ashamed that you'd think I'd be anything but nice brother dear, I'm not Damon!" she argues while pointing at her brother.  
"Hey!", pouted her twin. Secretly, he couldn't wait for the reaction. While he and Stefan now both hated Katherine, he wasn't too sure how his sister felt about her. They had been best of friends when she was human, but seeing no one had told Bella that Katherine had lied about being in the tombe for all those years, today was going to be a day of revelations.  
"Alright, so what's he talking about Stef? Why am I going to be mad?" she said turning back to her younger brother.  
"Elena, well, she's a human." said Stefan, knowing his sister wouldn't fully approve.  
Bella frowned, "well, it's not like you'll be the first to try it. It's not ideal, but you know, if anything goes wrong you can compel her out of your life"  
"And that is why you're my twin and not his" said Damon, "but that's not what I meant"  
Stefan glared at his brother while Bella looked at them both confused. They could all hear Stefan's new girlfriend descending down the stairs, and Bella started talking again to assure Stefan that nothing would make her instantly hate his new girlfriend "Look, Stef, she could have two heads, but as long as you're happy I'm-" She stopped speaking once Elena had reached the bottom step, standing next to Stefan.  
"Katherine?" she stared. Stefan took a step in front of his girlfriend and held her hand. "Bella, this is my girlfriend Elena. Elena, this is my sister, Bella"  
"It's really nice to meet you," Said Elena, giving Bella a sweet smile while extending her hand out.  
"Uh huh," Bella nodded. She stared for a few more seconds, making Elena uncomfortable. She tried to match Bella's stare with another smile but faltered after realizing that the eyes she was staring into were exactly the same as Damons. After a few more seconds Bella shook her head "So sorry," she said, meeting Elena's hand, "I promise I'm not mentally unstable you just look eerily similar to an old friend of mine" she trailed off.  
"Katherine?" said Elena, "yeah, I get that a lot" she nervously continued.  
"So you know?" replied Bella, "about us?" she said as she waved her hands over her fangs. Damon chuckled, "you see Katherine's doppelganger and the first thing you ask is if she knows you have pointy teeth? How about 'hey Stefan why are you dating my evil ex-best friends twin?' or something sisterly like 'oh hey stef are you sure you're not just using your repressed feelings from Katherine onto your new girlfriend?' or I don't know, possibly 'are you nuts?'"  
Bella just shrugged in response, "Don't get me wrong, I do think you're nuts Stef and possibly have some weird sort of repressed feelings about your not so dead, dead ex-girlfriend," she said, looking at her younger brother, "However," she started again, turning to Damon, "I have this thing called 'manners', Damon, which call for not being rude in front of Stefans guest. Didn't father teach you anything?" Damon simply rolled his eyes as he took a sip from his drink. "  
"Bella," said Stefan, his voice turning more serious. He knew now was the time to tell his sister that Katherine was still alive, before she found out herself.  
"What? I am the polite one, not him!" She said, pointing her finger towards Damon. She knew the action was childish, but she couldn't help it.  
"There's something you should know, about Katherine"  
"Oh boy," mumbled Damon, "now?"  
"What is it?" questioned Bella, ignoring her twin.  
Stefan looked at his brother for approval, and Elena squeezed his shoulder in encouragement. No one knew what Bella's reaction to the news about her ex best friend would be, but she had to be told before Katherine decided to make another appearance.  
"Katherine, well, she's not dead" he said uncertainty, "No shit sherlock, she's a vampire" said Bella as she rolled her eyes. Stefan looked to his brother again, but neither seemed to be able to find the words to explain themselves. Finally, hating the silence, Elena cut in.  
"Bella, a few months ago during the comet Damon opened the tomb to save Katherine, but she wasn't there. She was never locked in there with the rest of the vampires, she's been free this whole time. We didn't know until recently when Damon thought he kiss- when Damon did something. But she's back, and she was looking for a moonstone to break an ancient curse on a hybrid who's trying to kill me. We had her trapped in the tomb for a while, but a few weeks ago she was freed and we're not sure where she is not. I know this all sounds crazy, but you have to believe us."  
The female Salvatore seemed to stare at the other three inhabitants of the room for what seemed like ages, analyzing them all to see if they were telling the truth. Once she determined that was all they had to tell her, she spoke again. "I know," was all she said.  
"Excuse me? What?" said Damon, looking at his twin with a shocked face. His expression was mirrored by Stefan and Elena, all who couldn't believe what they were hearing.  
"I said, I know." said Bella, holding her ground.  
"What do you mean you know? You mean you somehow heard she was back tormenting us? Or you knew this whole time she wasn't in the tomb?" yelled her twin. Bella looked at her feet as she spoke, "I've known she wasn't in the tomb since 1864,"  
"What the hell Isabella?" yelled Damon, Bella knew she was in trouble with her brother, he never called her by her full name unless he was upset with her.  
"Please, before you get too angry, please you two just let me explain"


End file.
